列表的这些子集称为切片。 If L is a list, the expression L [ start : stop : step ] returns the portion of the list from index start to index stop, at a step size step. Basic Example Here is a basic example of list slicing. #Example: Slice from index 2 to 7 L = ['a', 'b'...
usesList+list: List+index: int+slice(from: int, to: int) : ListNegativeIndex+index: int+fromEnd: bool 结尾 通过本篇文章,我们学习了 Python 负数索引切片的基本概念和实现步骤。希望这对你理解序列操作有所帮助!在日常编程中,灵活运用负数索引切片将使你的输入输出操作更加高效简洁。继续探索吧,Python 的...
Python list slice negative step With a negative step, we take every nth element from the end. The start index must be greater than the end index. main.py #!/usr/bin/python vals = [-2, -1, 0, 1, 2, 3, 4, 5, 6] print(vals[5:0:-2]) print(vals[::-2]) print(vals[::...
Getting Sublists with Slices • spam[2] is a list with an index (one integer). • spam[1:4] is a list with a slice (two integers). >>> spam = ['cat','bat','rat','elephant']>>> spam[0:4] ['cat','bat','rat','elephant']>>> spam[1:3] ['bat','rat']>>> spam...
return self.data[index]else: msg = "{cls.__name__} indices must be integers"raise TypeError(msg.format(cls=cls))l = MyList(["My", "name", "is", "Python猫"])### 输出结果：key is : 3Python猫key is : slice(None, 2, None)data is : ['My', 'name']<__main__.MyList...
接下来,我们定义一个简单的 MyList ,并给它加上切片功能。(PS:仅作演示,不保证其它功能的完备性)。 从输出结果来看,自定义的 MyList 既支持按索引查找,也支持切片操作,这正是我们的目的。 3.3、自定义字典实现切片功能 切片是序列类型的特性,所以在上例中,我们不需要写切片的具体实现逻辑。但是,对于其它非序列...
self.data = anylistdef__len__(self):returnlen(self.data)def__getitem__(self, index):print("key is : "+str(index)) cls =type(self)ifisinstance(index,slice):print("data is : "+str(self.data[index]))returncls(self.data[index])elifisinstance(index, numbers.Integral):returnself.data...
print(py_list[slice_object])# ['P', 'y', 't']# contains indices 1 and 3 slice_object = slice(1,5,2) print(py_tuple[slice_object])# ('y', 'h') Run Code Output ['P', 'y', 't'] ('y', 'h') Example 5: Get sublist and sub-tuple using negative index ...
Another form of concatenation is with the application of thejoinmethod. To use the join method, we have to call it on the string that’ll be used for joining. In this case, we’re using a string with a space in it. The method receives a list of strings and returns one string with...
# using Slice operation Sliced_List =List[3:8] print("\nSlicing elements in a range 3-8: ") print(Sliced_List)#注意元素从第四个开始,包括第四个,不包括第九个 # Print elements from a # pre-defined point to end Sliced_List =List[5:] ...